| 摘要 |
PURPOSE:To enable early discovery of abnormality and others by always capturing deterioration in an insulator of a stator winding with an invariable measuring and monitoring of corona thereof during the service of rotary electric machine. CONSTITUTION:As a corona generated in the winding 1 of a stator develops in a detection resistance 8 passing through a band range 3 while the voltage of a commercial frequency as unbalance portion is provided, a corona discharge is taken with a high pass filter 9 and fed to a power board with a cable via an emitter floor 10. The power board removes the commercial frequency guided to the cable completely with a high pass filter 11 and a pulse voltage alone is amplifier 13 passing through a resistance damper 12 to discarn the maximum point of the phase to be measured with a phase gate 14. The waveform can be inspected visually with a synchroscope 17. The value of the corona is discriminated with a wave peak discriminator 15, counted with a counting rate meter 16 and recorded with a recorder 18. Thus, a highly accurate corona monitoring is possible. |
